mammalian cell line iBMK 176mM: yeast 238mM: E. coli 243mM mM
|Park JO et al., Metabolite concentrations, fluxes and free energies imply efficient enzyme usage. Nat Chem Biol. 2016 May 2. doi: 10.1038/nchembio.2077. p.6 figure 5aPubMed ID27159581
|Abstract: "Here [investigators] use isotope labeling to measure absolute metabolite concentrations and fluxes in Escherichia coli, yeast and a mammalian cell line. [They] then integrate this information to obtain a unified set of concentrations and ΔG for each organism."
|P.4 left column bottom paragraph: "Across the organisms, amino acids comprised the largest fraction of the metabolome (Fig. 5a) and were similar in intracellular abundances despite the presence of amino acids in the mammalian but not the microbial culture medium. Central carbon metabolites were the next most abundant, followed by nucleotides (including nucleotide-derived cofactors such as NAD+). The most abundant individual metabolite in each organism was glutamate, the amino group donor in many transamination reactions, whose high concentration may be required to drive transamination forward. Other abundant intracellular metabolites included reduced glutathione and pyruvate (Fig. 5a)." P.7 right column bottom paragraph: "In each of the studied organisms, the sum of all measured metabolite concentrations is around 200 mM, similar to the salt concentration in human plasma. Within this upper osmotic bound, an important determinant of absolute metabolite abundances is saturation of enzyme binding sites." iBMK=Immortalized Baby Mouse Kidney Epithelial Cells